bug#62333: 30.0.50; Issue with tree-sitter syntax tree during certain changes

[Dmitry Gutov]

On 25/03/2023 15:14, Eli Zaretskii wrote:
> > Date: Sat, 25 Mar 2023 15:00:24 +0200
> > Cc:wkirschbaum@gmail.com,casouri@gmail.com,62333@debbugs.gnu.org
> > From: Dmitry Gutov<dgutov@yandex.ru>
> >
> > On 25/03/2023 14:34, Eli Zaretskii wrote:
> > > Is there any real reason blink-matching-open narrows the buffer?  If
> > > we could remove that narrowing, the problem with the parser's taking
> > > notice of it would be gone.
> > Performance: to avoid scanning for the matching paren too far in the buffer.
> If that's the only reason, then tree-sitter based modes could widen
> back in their sexp-moving functions, since they use the parse data for
> this, right?

Not necessarily: it doesn't know the purpose for which the narrowing was 
applied. Could be for a mixed-major-mode thing, or some other purpose. 
Long lines?

Do we recall the exact design idea why tree-sitter visibility is limited 
by the narrowing bounds? Because if we wanted to widen in all similar 
situations, we might as well make it not obey the narrowing at all.